The CEMS on-line analyzer is a classic application of measuring principles! 　　

　　On-line continuous monitoring of emission concentrations and total emissions of pollutants from fixed sources has been achieved by the continuous on-line on-line monitoring of flue gas monitoring using extraction sampling, backscatter ash concentration measurements, leather hosting pneumatic flow measurements and computer network communication techniques. At the same time, technical improvements have been made in response to the country ' s relatively small coal species, high variations in coal, high discharge concentrations of pollutants and high flue gas humidity. It is also designed in accordance with national standards to provide a professional Chinese operating platform and a Chinese reporting function, multi-group simulations and a switch input output interface, which will make it possible to connect the on-site bus and use a variety of communication methods to make the system operational and flexible.

　　The CEMS, which is currently installed, contains various principles and measurement methods, such as the gaseous pollutant CEMS sampling method, which involves complete extraction systems, diluted extraction systems and direct measurements. Measurement principles relate to infrared spectroscopy, ultraviolet spectroscopy, chemiumscence. The particle CEMS involves opacity (silent), dispersion, scintillation, etc. The main principles of current speed measurement are leather hosting, ultrasound, heat sensors, etc. The temperature of flue gas is measured using platinum resistor or thermal voltometers. The oxygen content of the flue gas is a very important parameter, measured mainly by the oxidation method, magnetic techniques (magnetic wind, magnetic rectangular and magnetic voltage) and electrochemical methods.

　　1. Gaseous pollution systems

　　The gaseous contaminant CEMS is sampled mainly through complete extraction systems, diluted extraction systems and direct measurements.

　　Classic application

　　The complete extraction system uses a special heating sampling probe to extract the flue gas from the flue and pass through thermal transport, so that the smoke does not occur during the transport, and the flue gas is transported to the flue gas analyzer cabinet for dust removal, dehumidisation, etc., and then enters the flue gas analyzer for analytical detection.

　　The analytical principles used by the complete extraction system analyzer are mainly those of infrared spectroscopy absorption and ultraviolet spectroscopy absorption (the most widely applied principles of ultraviolet analysis), which absorb wavelengths using the characteristics of the contaminant molecules and allow different types of contaminants to be distinguished (e.g. SO2 absorbs 280 ~320 nm, NO absorbs 195 ~225 nm, 350 ~450 nm).

　　2. Particle measurement systems

　　The main principles of the particle CEMS are: the hysterometer and the photoscatter detector.

　　Classic application

　　The principle of the light dispersion detector is that when light is directed at particles, the particles are capable of absorbing and dispersing the light, thus diverting the light from its input path. The intensity of the dispersion light is related to the observation angle, the particle size of the particle, the refraction rate and shape of the particle, and the wavelength of the input light. The light-scatter analyzer is designed to measure the intensity of the dispersive light at an angle that deviates from the light. The intensity of the scattering light in all directions is related to the particle distribution and shape of the particles. Similarly, water drops have an impact on instrument measurements, and the instrument needs to be calibrated using manual matching.

　　3. Oxygen-containing measurement systems

　　Measurements of emissions of flue gas contaminants must measure the actual concentration of oxygen so that the emission concentration can be converted.

　　Aerobic oxide analyzers usually have direct measurements, i.e. measuring probes in the flue. There is also a flue extraction pattern, that is, sampling probe, which inserts a pipe, and a measuring pool is placed in the analysis I (sampling pipeline required) at a certain distance from the pipe.

　　The oxen oxide analyzer measures the principle on which O2 is based: in electrolytics, electricity flows between electrolytes or gases containing different concentrations of compounds due to different chemical levels. In typical measuring ponds, ZrO2 produces oxygen ion as electrolyte and high temperature catalysts. On both sides of the pool, a layer of platinum is burned to form electrodes on the flue gas side and reference electrodes in contact with gases containing O2 reference gases (usually air). The temperature of the pool must be heated to about 600°C.

　　The O2 can be measured with great precision and reliability. Low-cost, higher accuracy requires long maintenance.

　　Magnetic Oxygen Analyzers (MAAs) are used to measure O2 using the smooth magnetic properties of oxygen.

　　The principle of chemical batteries is to measure the oxygen content as the current produced by electrochemical fuel cells is comparable to the oxygen in the samples. The Electro-chemical dye batteries are less sensitive to cross-sensitivity, with sensors having an operational life of about 6-18 months and an average life of 12 months. In general, this type of sensor is used in portable oxygen analyzers and is an ideal portable instrument. The O2 electrochemical fuel sensor has been used in the on-line smoke monitoring system, and the above-mentioned instrument forms a continuous analyzer.

　　Flow speed measurement system

　　Flow speed measurements of pneumatics or piping are used in leather hosting differential pressure, thermal sensor system, ultrasound flow speed detection.

　　Classic application

　　The S-pelt hosting consists of two small tubes, one in the direction of the flow of the gas, measuring the shock or kinetic pressure of the gas, and also measuring the temperature and pressure of the flue gas in order to accurately measure the volume flow. Regular condensed air rebreaths can overcome the problems of particles and droplets that cause proxies to jam or quagmire. Accurate measurement of low pressure differentials is difficult for the S leather host, with the actual measurement of a minimum pressure difference of about 5 pa and a minimum flow rate of 2 ~ 3 m/s that can be measured.

　　5. Frozen moisture measurement system

　　Since our country measures concentrations and emissions of pollutants using standard measures under dry smoke, data on flow, particulate matter concentration, SO2, Nox concentration, O2 concentration, etc., need to be revised for dry smoke based on measured flue moisture.

　　The measurements of flue moisture are mainly direct measurements and dry wet oxygen.

　　Direct measurement: Use of electric-capable sensors, direct insertion of probes into the pipe, protected by specially designed filters around the probes.

　　Dry-wet oxygen: The concentration of wet oxygen in the flue pipe is usually measured directly using an inserted oxidized peroxide probe, the temperature of the flue gas removed from the smoke is removed and humidized using a full extraction method, the dry oxygen content is measured and the flue-moisture is calculated.